Probe for skin high frequency treatment

ABSTRACT

The invention concerns a probe for applying a high frequency electromagnetic energy flux on the skin through a mixture of conductive gel and a treatment product, designed to cause the treatment product to penetrate into the skin. The probe is provided with a non-conductive bearing surface ( 14 ), having a plurality of openings ( 6 ) around or in the proximity of which inductor elements ( 5 ) arranged in successive layers emit an electromagnetic field. The openings ( 6 ) emerge through an orifice ( 3 ) and contain the gel/treatment product mixture whereof the penetration into the skin is activated by the electromagnetic field. Advantageously, the probe further comprises at least one source of laser electromagnetic radiation ( 8 ) arranged inside or aligned with at least one opening ( 4 ) emerging in the bearing surface ( 14 ), so as to act jointly with the electromagnetic radiation emitted by the inductor element ( 5 ).

TECHNICAL FIELD

The invention relates to treatment of the skin by high-frequencyelectric means possibly associated with a source of laserelectromagnetic radiation, particularly for so-called “permanent” or“long lasting” depilation, as well as for regrowth of hair.

STATE OF THE ART

WO 93/04636 describes a process based on the observation that by mixinga conductive gel of the usual type used for the application ofultrasound probes to the skin, with a treating product, for example alotion producing atrophy of the hair roots, it is possible bytranscutaneous induction at high-frequency to cause the treating productto penetrate into the follicles (pores) and the hair stems and hencecarry out a treatment.

This method hence enables a treatment of the skin to be carried out,notably a cosmetic treatment, for example to achieve long lastingdepilation, and which moreover allows a punctual and effectiveapplication down to the follicles without a delicate manualintervention.

To carry out the method, WO 93/04636 also describes an apparatuscomprising a handleable member for contacting the skin, having anon-conductive body provided with a bearing surface adapted to beapplied to the skin. This surface comprises a plurality of discreteconductive electromagnetic emission points for example formed by exposedparts of turns of a solenoid embedded in the body of the contact member.These points are accessible through openings in this surface, and arepreferably set back with respect to the latter, so that during use ofthe apparatus, these points may Contact conductive gel applied to theskin. These discrete emission points emit a high-frequency flux ofelectromagnetic energy, advantageously a pure emissive current suppliedby a high-frequency oscillatory power circuit.

To carry out the same method, WO 96/03928 describes a flexibleapplicator probe able to conform to the part of the body to which it isapplied, comprising non-conductive lower/internal and upper/externalparts. At least the lower/internal part is provided with cavities havinga plurality of discrete conductive electromagnetic emissive points orareas formed by parts of turns of a coil which are set back in relationto the probe's lower/internal surface.

Another technological approach described in French patent 2 589 067 is amethod and apparatus based on the observation that the application tothe skin of an electrical field in combination with a laserelectromagnetic radiation leads to a modification of the skin'sabsorption properties.

SUMMARY OF THE INVENTION

The present invention relates to a probe for applying a flux ofhigh-frequency electromagnetic energy to the skin, useful notably in themethod described in WO 93/04636 or in French patent 2 589 067, or in anyother method necessitating application of a conductive gel, this probebeing provided with a non-conductive bearing surface adapted to beapplied to the skin, this surface having in its thickness at least onecavity (or opening) that opens out via an orifice into the bearingsurface as well as at least one inductor element for inducing anelectromagnetic field and arranged to emit an electromagnetic fieldthrough said cavity and its orifice.

The probe according to the invention is characterized in that saidinductor element is located in its thickness at an intermediate level ofthe depth of the cavity, this inductor element extending at least partlyaround and/or being in the proximity of said cavity's wall.

Further characteristics of the probe according to the invention are setout in claims 2-15. The invention also pertains to the use of this probefor cosmetic treatments of the skin, as set out in claims 16-18, and toa method of cosmetic treatment of the skin according to claims 19-23.

When the probe is used, a mixture of gel/active treating product isapplied onto the skin to be treated and/or into the cavities of theprobe's bearing surface so that this mixture acts as conductiveinterface between the prober's bearing surface and the skin.

The flexible applicator probe according to the invention has numerousadvantages. For instance, the intermediate arrangement of the inductorelement for inducing the magnetic field allows this cavity to beenlarged and/or to make it a through-opening traversing the probersthickness, so that a source of a laser beam can be fitted within theprobe's thickness or on its upper/outer surface. This arrangementfacilitates the simultaneous application of an electromagnetic field anda laser electromagnetic radiation onto the skin, as described in Frenchpatent 2 589 067. Moreover, the intermediate arrangement of themagnetic-field inductor element permits easy manufacture of the probesby perforation. Additionally, the arrangement of the magnetic-fieldinductor elements at least partially around and/or in the proximity ofthe cavities' wall enables them to be arranged in successive layers,thereby allowing multiplication of the number of theelectromagnetic-radiation missive points situated in each cavity. Thisarrangement furthermore enables the electromagnetic radiation producedby the multiple emission points to act on a greater quantity of thegel/treating product mixture in the cavities. This increases theintensity of the electromagnetic field applied to the gel/treatingproduct mixture and to the skin, hence increasing the treating power ofthe applied products.

The electromagnetic field inductors are for example made of flattenedwindings, or of a network or grid of conductive material. The conductivematerial is preferably a conductive sheet of silicone resin, a fabric ofconductive fibers such as carbon fibers, or a non-woven textile made ofconductive fibers.

In embodiments comprising a laser electromagnetic radiation source, thissource can be constituted either by a laser-emitting diode housed in thethickness of the probe or on its upper face, or by an optical fiberconnected to a laser source external to the probe. In these embodiments,one possible arrangement is to arrange the cavities in the supportsurface in a pattern or along lines forming various geometrical figures,and to position the laser sources in a regular manner in the saidpattern or along said lines.

If desired, the applied flux of electromagnetic radiation follow aprogram determined by the means for generating electrical impulses andthe means for exciting the laser sources, for example alternating thetwo types of electromagnetic radiation and/or varying their intensity.

The probe according to the invention may be used, in combination With atreating gel, for the cosmetic treatment of the skin, in particularlong-lasting depilation, baldness, couperosis, varicose veins andcapillaries.

BRIEF DESCRIPTION OF THE DRAWINGS

Further features of the invention will be apparent from the followingdescription, given by way of example, with reference to the drawings inwhich:

FIG. 1 is a perspective view of a first embodiment of probe according tothe invention, made of an elongate handleable member with a lasersource;

FIG. 2 is a partial view in axial cross-section along line II—II of theprobe shown in FIG. 1;

FIG. 3 is a view from below of a sheet forming part of a secondembodiment of probe according to the invention;

FIG. 4 is a cross-sectional view of a probe including the sheet of FIG.3, along line IV—IV of FIG. 3;

FIG. 5 is a view from below of a third embodiment of probe according tothe invention; and

FIG. 6 is a cross-sectional view along line VI—VI of the probe shown inFIG. 5.

DETAILED DESCRIPTION

The probe shown in FIGS. 1 and 2 comprises a handleable elongate contactmember 1 connected at one of its ends to a current lead 2 and which hasat its other end a circular bearing surface 14. The current lead 2supplies an inductor element 5 for generating an electromagnetic field,recessed relative to the bearing surface, and emitting via severalcavities (or openings) 6, namely six of them in this example, whichcavities lead into the bearing surface 14. The inductor element 5 forgenerating the electromagnetic field is situated at an intermediatelevel in relation to the depth of the cavities 6, this inductor elementextending at least partially around and/or in the proximity of the wall7 of these cavities. A source 8 emits laser electromagnetic radiationthough an additional opening 4 situated along the member 1's axis,leading centrally into the bearing surface 14, i.e. centered relative tothe cavities 6. The cavities 6 typically have a diameter between 3 mmand 6 mm whereas the opening 4 for the emission of laser radiationtypically has a diameter between 6 mm and 10 mm.

The embodiment shown in FIGS. 3 and 4 is a flexible probe 9 comprisingseveral (as shown, four) flexible layers of rubber between which aresandwiched several (as shown, three inductor elements 5 occupying thequasi-totality of the flexible probe, except its non-conductiveperiphery 10. The inductor elements 5 are arranged in several layerselectrically connected together by connections 11, and connected to acurrent lead-in, not shown. FIG. 4 shows two inductor elements 5′situated at intermediate levels of the depth of cavities 6, as well asan optional inductor element 5″ situated at the bottom end of thecavities 6. Each inductor element 5 is for example constituted of awoven fabric 12 of carbon fibers having perforations 13. The flexibleprobe 9 has a lower/inner face constituting the bearing surface 14, andan upper/external face 15. The cavities 6 are situated in the thicknessof the sheet of flexible material and open into the lower/inner face 14by orifices 3. As a modification, shown in dashed lines in FIG. 4, thecavities 6 are perforated through-openings, which simplifiedmanufacture.

The embodiment shown in FIGS. 5 and 6 is a flexible probe 9 comprisinglaser-emission sources 8. As previously, the probe is in the form of aflexible sheet having a lower/inner face forming the bearing surface 14,and an upper/external face 15. The probe comprises, on the one hand,blind cavities arranged in a repeating pattern forming geometricalfigures and, on the other hand, additional through-openings 4 disposedin a regular fashion relative to said pattern, the latter permittingpassage of laser electromagnetic radiation 16 emitted by source 8. Thecavities 6 are distributed about the through-openings 4 so as to obtaina uniform distribution of the laser radiation. The probe 9 is connectedby a current lead 2 to means for generating electrical impulses,connected to the inductor elements 5, as well as to means for excitingthe laser sources 8. Examples of these two types of means are describedfor example in French patent 2 589 067. Furthermore, the laser sourceadvantageously comprises a lens by which the laser beam can bedefocalized.

If desired, the different embodiments of probe 9 further include aswitch arranged so as to activate the flux of high-frequencyelectromagnetic energy and excitation of the laser sources when theprobe comes into contact with the skin and/or with the gel. This featureincreases safety when the probe is used, in particular for embodimentscomprising one or more electromagnetic laser sources. This switch,connected to the means for generating electrical pulses and to the meansfor exciting the laser sources via the current lead 2, can bemechanical, opto-electronic, of the impedance/capacitance type, reactingto the skin and/or to the gel, or of any other type known to the skilledperson. As a variation, this switch is connected to a device for timingthe switching on or off of the application of the flux ofelectromagnetic energy when the probe comes into contact with the skinand/or gel, or when it is removed.

Typically, the pulses creating the electromagnetic field are staticactivation pulses of duration from 1 microsecond to 1 second, And havingmodulated frequencies with constant ratio from 5 Hz to 1000 Hz. Thelaser radiation normally has an energy from 0.5 mW to 150 mW. However,higher energies can be used, say 500 mW or more, as long as the beam isdefocused by a lens to cover a field of larger surface area.

The loaded gel used for the treatment method is preferably composed of anon-polymerisable conductive gel of a type used usually for couplingultrasound probes with the skin, mixed with a treating product. The gelhas a neutral pH and is for example based on glycol-carboxyvinylictrithanolaminepropylene. The composition of the treating product dependson the desired action. For depilation, one may choose a productproviding a progressive atrophy of the hair root, for example apost-depilatory lotion of the type usually used immediately afterwax-depilation, as well as during the subsequent days. Such lotionscomprise plant extracts, essential oils, demineralised water andpossibly other components, for example polyoxyethylenes. These products,known sometimes is “hair regrowth moderators” are non-toxic andgenerally risk-free when used.

For treating baldness, the gel can be mixed with, for example,minoxydil, or any other product promoting hair regrowth. A mixture of50:50 volume % of gel and minoxydil has given satisfactory results.

In order not to diminish the conductive properties of the gel, thequantity of active or treating product will in general not exceed 50weight % of the gel, usually less than 25% (% by weight=, % by volume).Alcohol, sodium chloride and/or other substances may be added to improvethe conductivity of the product and/or as conserving agents.

Tests have shown that applying high-frequency energy to the treatingproduct alone or to the gel alone does not produce any special effect,whereas with the mixture a good penetration of the treating productcarried by the conductive solution derived from the gel is obtained. Itappears that the flow of electromagnetic and electric energy follows thepath of least resistance: through the gel and conductive lotion mixtureapplied to the surface of the skin, and then, around the hair root, onlythrough the conductive lotion which alone penetrates into the follicleand the stem of the hair. The gel allows a progressive release of theactive lotion and penetration thereof, under the conjugated action ofthe electromagnetic and electric fields. In the embodiments havingsuccessive layers of inductor elements, the multiplication of the numberof points of emission of the electromagnetic field and the cavitiesamount of the gel/product mixture present in the openings allow a morecomplete penetration of the treating product. This effect is furthermorereinforced by the adjunction of a laser electromagnetic radiation.

As illustrated in FIGS. 1 and 6, the electromagnetic-field inductorelements 5 also surround the through-openings 4, and form a part ofthese openings walls. Thus, the gel in these openings 4 is both ionizedby the action of the electromagnetic field and traversed by the laserbeam, This simultaneous action produces a synergistic affect andpromotes a prolonged active duration without danger to the skin.

Advantageously, the probe according to the invention forms part of a setincluding: one or more rigid probes according to the invention adaptedto treat different parts of the body, each rigid probe comprising alaser source (see FIG. 1) or several laser sources arranged in a rigidhandleable member, for instance three sources in cavities 4 arrangedsymmetrically about the member's axis; several flexible probes ofdifferent dimensions, with a laser source (for example as in FIGS. 5 and6) or without a laser source (for example as in FIGS. 3 and 4, or asdescribed in WO 96/03928); and at least one needle fitment formicrothemolysis or electrocoagulation. All of these probes and fitmentsare interchangeable and can be controlled by a central unit, enabling agreat variety of different treatments.

What is claimed is:
 1. A probe for applying a flux of high-frequencyelectromagnetic energy to the skin, the probe being provided with anon-conductive bearing surface (14) adapted to be applied to the skin,this surface having in its thickness at least one cavity (6) that opensout via an orifice (3) into the bearing surface as well as at least oneinductor element (5,5′) for inducing an electromagnetic field andarranged to emit an electromagnetic field through said cavity and itsorifice (3); wherein said inductor element (5,5′) is located in saidthickness at an intermediate level of the depth of the cavity (6), thisinductor element extending at least partly around and/or being in theproximity of said cavity's wall; and wherein said probe comprises atleast one source (8) of laser electromagnetic radiation arranged in oraligned with at least one opening (4) leading into the support surface,in such a manner as to act together with the electromagnetic radiationemitted by said inductor element(s) (5, 5′).
 2. A probe according toclaim 1, characterized in that the inductor element(s) (5, 5′) is/areconstituted of flattened windings.
 3. A probe according to claim 1,characterized in that the inductor element(s) is/are constituted of asheet of conductive material having perforations (13) or cut-outsforming a part of said cavity (6).
 4. A probe according to claim 1,characterized in that the inductor element(s) (5,5′) is/are constitutedof a woven fabric including conductive fibers.
 5. A probe according toclaim 1, characterized in that the inductor element(s) (5, 5′) is/areconstituted of a non-woven fabric including conductive fibers.
 6. Aprobe according to claim 1, characterized in that the inductorelement(s) (5, 5′) is/are constituted of a woven fabric of carbonfibers.
 7. A probe according to claim 1, characterized in that at leasttwo inductor element(s) (5′) are arranged in discrete layers spacedapart from one another in the thickness of the probe.
 8. A probeaccording to claim 7, having at least one blind cavity (6) leading intothe bearing surface (14), characterized in that it further comprises anadditional inductor element (5″) situated at the bottom of the blindcavity/cavities (6).
 9. A probe according to claim 7, characterized inthat it is formed of several discrete layers piled as a sandwich andincluding through-holes (4, 6) produced by perforation.
 10. A probeaccording to claim 1, characterized in that the laser source comprisesat least one laser-emitting diode integrated in the probe, or at leastone optical fiber connected to at least one laser-emitting deviceexternal to the probe.
 11. A probe according to claim 1, characterizedin that it is in the form of a handleable member (1) for contacting theskin, this member being formed of an elongate body one end of whichforms the bearing surface (14).
 12. A probe according to claim 1,characterized in that it is in the form of a flexible sheet able toconform to a part of the body against which it is applied, this flexiblesheet having a lower/inner face including the bearing surface (14), anda non-conductive upper/external face (15), at least said lower faceincluding said bearing surface (14).
 13. A probe according to claim 1,characterized in that cavities (6) leading into the support surface arearranged in a repeating pattern or in alignments forming variousgeometrical figures, and in that the laser sources (8) are arrangedregularly relative to said pattern or lines.
 14. A probe according toclaim 1, characterized in that it further includes a switch arranged soas to activate the flux of high-frequency electromagnetic energy, andalso excitation of the laser source, when the probe comes into contactwith skin and/or with the gel.
 15. A method for the cosmetic treatmentof the skin, using the probe according to claim 1, comprising: (a)applying to the skin a mixture of conducting gel and a treating productfor the cosmetic treatment of the skin; (b) emitting a high-frequencyelectromagnetic current from the laser source of the probe into the skinto cause the product to penetrate into the pores of the skin; and (c)applying a laser electromagnetic radiation from the laser source of theprobe simultaneously or non-simultaneously to the skin in order toincrease the effect of the treating product, its duration of action andits penetration.
 16. A method according to claim 15 for long-lastingdepilation, characterized by applying to the skin a mixture ofconducting gel and a product able to atrophy the hair roots.
 17. Amethod according to claim 15 for the cosmetic treatment of baldness,characterized by applying to the skin a mixture of conducting gel and ahair-regenerating product.
 18. A method according to claim 15 for thecosmetic treatment of couperosis, characterized by applying to the skina Mixture of conducting gel and a product able to atrophy thecapillaries.
 19. A method according to claim 15 for the cosmetictreatment of varicose vein and capillaries, characterized by applying tothe skin a mixture of conducting gel and a product able to atrophy theveins and capillaries.